To milwaukee gas



Sept. 22, 1931.

R. H. sHA'DRVlCK THERMOSTATIC CONTROL Filed Jan. 6, 1927 Patented Sept.22, 1931 TATES PATENT OFFICE RICHARD H. SHADRICK, OF MINNEAPOLIS,MINNESOTA, ASSIGNOR, .BY MSNE ASSIGN- MENTS,'T0 MILWAUKEE G-AS SPECIALTYCOMPANY, OF MILWAUKEE, WISCONSIN,

A CORPORATION THERMOSTATIC CONTROL Application filed January 6, 1927.Serial No. 159,350.

line to the main burner. A further objectis to provide means of anextremely simple and practical nature for re-openin such valve andresetting the thermostatica y operated mechanism to its initialoperative position. A still further object is to provide means foradjusting the operative sensitiveness of the device. Still further andmore specific objects will be disclosed in the course of the followingspecification, reference being had to the accompanying draw-- ings, inwhich:

Fig. 1 is an elevation showing the adaptation of my device to the burnerand fuel feed pipe of a common type of water heater, various parts beingshown in section.

Fig. 2 is an enlarged elevation of the control unit, as seen in Fig. 1but from the opposite side, various parts bein broken away, while othersare in section, or purpose of illustration.

Fig. 3 is a sectional elevation, as seen on the irregular line 3-3 inFig. 2.

Referring to the drawings more particularly and by reference charactersA designates the casing of a hot water heater, having a storage tank Bin which water is heated by a main burner C, fed with fuel from a pipeline D. The casing A may be insulated, as 'at E, to help retain the heatin the water. The pipe line D is provided with a valve F, which, asshown, is a hand valve, but may be avvalve of any other type without inany way interfering with the objects or functions of my inventions. Imight add that the present invention fembodies several improvements overthe constructions shown in my copending patent applications Ser. No.50,246, filed Aug. 14, 1925, for thermostatic cut out for gas valves andthe like now Patent No. 1,679,169, and Ser. No. 60,- 632, filed October5th, 1925, for valve actuator, now Patent N o. 1,698,281; both of whichpatents show earlier designed thermostatic pilot control devices ofsomewhat similar natures.

Cut into the pipe line D, in advance of the valve F, is a second valve4, having a core 5 and suitable means, such as a sprin 6, for yieldinglyholding the head 7 of the core in closed contact with the seat of thevalve. Projecting through a neck 8, of the valve, is a pin 9, which,when depressed, holds the valve open against the resistance ofthe spring6. Valves of this type are of common and well known construction.

Secured to and carried by the neck of the valve 4, and preferablysecured by a nut 10, is a frame creasing consisting of an end wall 11,and an inverted, substantially `U-shaped housing 12, having a ,curvedtop and open at its bottom and one end. Secured, as by screws 134 to thehousing 12, is a pilot tube 14, having a goose neck eX- tension 15, atone end, which is connected with the main supply pipe D, above the valve4 so that it will not be influenced by the open 4or closed position ofthis valve. The other end of the tube is provided with -a burner tip 16,which may be of any suitable construction, but which, in Fig. 2, isshown as of the Bunsen type. The pilot tube is extended through anaperture 17 in the heater Wall A, E, so that the burner or tip 16 willbe in a lighting position with respect to the main burner C.

The valve 4 is opened and held open by a lever member 18, carried by ashaft 19, which is journaled in the side walls of the casing 12. Thisshaft is provided with an arm or handle 20, by which it may be turned toraise the lever to the vertical position shown in Fig. 2. The lever 18is preferably provided with a` cam acting hump 21,I for engagement withthe valve pin 9, and, as the shaft center 19 1s practically in the sameplane with the pin 91t will be seen that when the lever is in its upperposition the resistance of the spring projected pin 9 will be veryslight and that very little effort will be requlred to hold the leverup, yet when the lever 1s released, the spring 6 will quickly andeffectively project the pin and reseat the valve, moving the lever 18and the arm 20 to the dotted line positions shown in Fig. 2. g

The lever 18 is normally held 1n. its upstanding position by engagingagainst the end of a strip of thermostatic metal 22, the same beingsecurely fastened, at its other end, to the pilot tube 14, by a Screw2.3. This strip is of the well known type 1n which two layers of metal,having different coecients of expansion, are fused together, so thatwhen subjected to variable temperatures the strip as a whole will bendor be slightly distorted, whereby the free end will be moved up anddown. A set screw 24, having a lock unit 25, is provided, for adjustingthe operative position and sensitiveness of the strip. Tt will be notedthat a partv of the strip 22 is in direct contact with the pilot tubewhile the rest of it 1s parallel with and adjacent to the tube, theobject being to so locate it that it will retain substantially the sametemperature of the tube. The tube acts as a heat conductor and is warmedby t-he heat of the pilot flame suiiiciently so that it will also keepthe .thermal strip 22 at a temperature where its free end will be in aposition to lengage the lever 18, as shown in Fig. 2, to keep the valveopen. Now then if the pilot light goes out, when the burner C isinactive, the pilot tube will quickly cool, and, as the strip 22 willthen also cool off, it will bend upward, releasing the lever 18, andthus permit the valve 4 to snap closed. This will cut off the supply offuel to the valve F and the main burner, with a result that the mainburner cannot be relit until the pilot burner has first been lit. Thiscondition will readily be discovered, even in a remotely controlledvalve F, because the operator will not be able to draw any hot water. Torestore the parts to their original conditions the operator relights thepilot burner and as soon as the tube 141 and strip 22 are warmed by theflame he then pulls the handle 20 up until the lever 18 snaps behind theend of the now depressed strip 22.

It may be noted that as the pilot tube 14 acts as a heat conductor it isunnecessary to provide any other element for that purpose. It may alsobe noted that the strip 22 is removed from the influence of the intenseheat of the main burner and thereby its sensitive characteristics arepreserved, which is not the case where such metal is subjected to highor extreme changes in temperature. Tt may also be noted that while it ispreferable, in some instances, to secure the fuel supply for the pilot,from the main pipe D, in advance of the valve 4, it is also possible andfeasible, in other instances, to connect the pilot tube with the supplypipe, below the safety valve e, but in advance of the main valve F. Inthe latter instance, when the pilot goes out, then the valve 4 cuts offall possible fuel supply to both burners., But, as the escape of`unburned `fuel through the pilot burner is quite insignicant, in thearrangement shown, it is never dangerous, especially as heaters of thistype are usually connected up with fiues which carry off such minorquantities of escaping gases.

It is understood that suitable modifications may be made in the generaldesign and structural details of the invention as herein shown anddescribed, provided, however, that said modifcations come within thespirit and scope of the appended claims.

Having now therefore fully shown and described my invention, what Iclaim to be new and desire to protect by Letters Patent 1s:

1. A device of the character described, comprising a valve having aspring projected valve pin, a leverv having a cam portion for engagingthe valve pin to open the valve.

`said lever having a fulcrum axis which is substantially in alignmentwith the valve pin, and thermostatically operated means for releasablysecuring the lever in a predetermined position, said means including astrip of bi-metal having end contact with the lever and which upon beingsubjected to predetermined temperature will entirely free itself fromthe lever thus permitting a quick closing action of the valve.

2. The combination with a valve having a tendency 'to close and a pilottube having at `one end a burner, a member for holding the valve open, astrip of thermally responsive metal extending parallel with the tube andiny close proximity thereto so as to be influenced by the heat of thetube but removed from direct influence of the pilot burner and beingrigidly mounted at one end whereby the other end is rendered movable,said member being releasably secured by said other end of the metal, andso arranged with respect thereto that it may be snapped into engagementtherewith, and means for adjusting the operative sensitiveness of thestrip of thermally responsive metal.

3. The combination with a yieldably closed valve, of a lever actingmember for opening and holding the valve open, a pilot tube having aburner tip at one end, a strip of thermally responsive metal arrangedparallel with and adjacent to the pilot tube so as to be subjected tothe temperature thereof but removed from direct inuence of. the burnerame at said tip, one end of said strip being stationary while the otheris movable, said movable end being arranged to releasably retain thelever acting member in its valve opening position, and means foradjusting the operative sensitiveness ofthe metal strip.

4. The combination with a valve in a pipe, said valve having ayieldingly projected valve stem, of a casing secured on and carried bythe valve, a lever member pivotally mounted in the casing and having acam acting portion engageable endwise against the stem to -open thevalve, a pilot tube extending from the pipe and through the casing andhaving a burner tip at its end, a thermally responsive element securedto the tube and extending into the casing, in a direction away from theburner tip, for tripping engagement with the lever, whereby toreleasably hold the same with the valve in its open position.

5. The combination with a valve in a pipe said valve having a yieldinglyprojecte valve stem, of a casing secured on and carried by the valve, alever member pivotally mounted in the casing and 'having a cam actingportion engageable endwise against the stem to open the'valve, a pilottube extending from the pi'pe and through the casing and having a burnertip at its end, a thermally responsive element secured to the tube andextending into the casing, in a direction away from the burner tip, fortripping engagement with the lever, whereby to releasably hold the samewith the valve in its open position, and means, operative at theexterior of the casing, for operating the lever to open the valve.

6. The combination including a main burner, .a pipe for supplying fuelthereto, a main valve and a second valve in said pipe, a heat conductingpilot tube having a pilot burner at one end, for lighting the mam pilottube warm, means including a thermally responsive element anchored onand in direct contact with the tube in a position burner and fornormally keeping the` jected valve pin, a lever having a curved camportion surface for engaging the valve pin to open the valve, said leverhaving a fulcrum axis disposed in a position substantiallyin alignmentwith the valve pin, and thermostatically operated means for releasablysecuring the lever in a predetermined position, said means including astrip of bimetal normally holding the lever in its valve openingposition and which upon being sub` jected to a predetermined temperaturewill release the lever to'permit the valve to close. In testimonywhereof I aiiix my signature.

RICHARD H. SHADRICK.

removed from direct influence of the main burner, for effecting aclosing of the `second valve when the pilot burner'is extinguished andthereby permitting the pilot tube to cool, 'aid means including 'a leveracting member one end of which has direct releasable contact with theelement.

7 A device of the character described, comprising a valve having aspring pro-

